Discharge head for a fixed fire extinguishing system

ABSTRACT

A discharge head for use in a fixed fire extinguishing system including a body member having an inlet and an outlet for receiving and discharging fire extinguishant, and a plug member normally retained in the body member by a latching assembly for preventing the flow of extinguishant through the body member. The latching assembly is adapted to release the plug member in response to a fire occurring in the vicinity of the body member, thus permitting the discharge of the plug member from its flowpreventing position. A fusible member cooperates with the plug and is adapted to fuse at a predetermined temperature to permit the flow of extinguishant through the body member independent of the operation of the latching assembly.

United States Patent [191 Livingston 11] 3,821,986 "[451 Jul 2,1974

[ DISCHARGE HEAD FOR A FIXED FIRE EXTINGUISHING SYSTEM [75] Inventor:William L. Livingston, Sharon,

Mass.

[73] Assignee: Factory Mutual Research Corporation, Norwood, Mass.

Primary Examiner-M. Henson Wood, Jr.

Assistant Examiner-John J. Love Attorney, Agent, or FirmLane, Aitken,Dunner and Ziems 5 7] ABSTRACT A discharge head for use in a fixed fireextinguishing system including a body member having an inlet and anoutlet for receiving and discharging fire extinguishant, and a plugmember normally retained in the body member by a latching assembly forpreventing the flow of extinguishant through the body member. Thelatching assembly is adapted to release the plug membet in response to afire occurring in the vicinity of the body member, thus permitting thedischarge of the plug member from its flow-preventing position. A fusible member cooperates with the plug and is adapted to fuse at apredetemiined temperature to permit the flow of extinguishant throughthe body member independent of the operation of the latching assembly.

12 Claims, 2 Drawing Figures BACKGROUND OF THE INVENTION This inventionrelates to a discharge head, and more particularly to a discharge headadapted for use in a fixed fire extinguishing system.

Various types of discharge heads have been proposed for use in fixedfire extinguishing systems. The most common of these is a sprinkler headwhich incorpo rates a fusible member which is adapted to release a plug,or the like, in the head in response to a predetermined fire situationoccurring in the vicinity of the head. The fusible member must beisolated from the plug due to the fact that the latter is in contactwith the water, or other extinguishant, and is therefore at atemperature that is too low to permit effective operation of the fusiblemember if it were in a direct heat exchange relation with the plug.Therefore, a latching assembly is often employed to provide a connectionbetween the plug and the fusible member to permit the latter to beisolated from the former. The latching assembly is adapted to releasethe plug upon collapse of the fusible member due to the heat of the fireand permit a discharge of the plug and a resultant discharge ofextinguishant from the head.

However, these discharge heads suffer from thefact that, due to theirrelatively long periods of inaction, the latching assembly may becomejammed, or otherwise inoperative, due to rust, dirt, grime, etc.collecting thereon. As a result, the entire head may be renderedinoperative despite the fact that the fusible member perates in a normalmanner.

SUMMARY OF THE INVENTION It is therefore an object of the presentinvention to provide a discharge head utilizing a latching assembly toconnect a plug member to a fusible member, yet which is operable in theevent the latching assembly becomes inoperative.

Towards the fulfillment of these and other objects, the discharge headof the present invention comprises a body member having an inlet forconnecting to a source of extinguishant and anoutlet for saidextinguishant; a plug means disposed in said body member; latching meansfor latching said plug means in a position preventing the flow ofextinguishant through said body member, said latching means beingresponsive to a predetermined fire condition in the vicinity of saidbody member for permitting the release of said plug means from itslatched position and the resultant flow of extinguishant through saidbody member; and means cooperating with said plug means in said latchedposition for permitting the flow of extinguishant past said plug meansin response to a fire condition different from said predetermined firecondition.

BRIEF DESCRIPTION OF THE DRAWINGS Reference is now made to theaccompanying drawings for a better understanding of the nature andobjects of the present invention. The drawings illustrate the best modepresently contemplated for carrying out the objects of the invention andare not to be construed as restrictions or limitations on its scope. Inthe drawings:

FIG. 1 is a cross-sectional view of the discharge head of the presentinvention; and

. I 2 FIG. 2 is an enlarged partial view of the discharge head of FIG.1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, thedischarge head of the present invention is shown in gen-era] by thereference numeral 10 and comprises a cylindrical body 12 having an upperend portion which is internally threaded as shown at 14 for connectionto a source of extinguishant such as water, and a lower end portionwhich defines an outlet orifice 16 of a reduced cross-section. A pair ofspiral vanes 18a and 18b are fixed within the body 12 for imparting aswirling motion to water fiowing downwardly therethrough in aconventional manner. Thev vanes 18a and 18b support a hollow central hub20 which, in turn, slidably supports a rod 22 having a head assembly 24fixed on its lower end. The head assembly 24 operates to block theoutlet orifice l6 and will be described in detail later.

The rod 22 is latched in the position shown in FIG. 1 by a latchingassembly shown in general by the reference numeral 30 in FIG. 1. Thisassembly includes a rod 32 which slidably extends through an externallythreaded boss 34 projecting from the side of the body 12. One end of therod 32 extends through the vane 18a and the wall of the central hub 20into a slot 36 in the 1 rod 22 to latch it in the position shown in FIG.1.

A sleeve'38 is threaded on the end of the boss 34. The outer end of thesleeve 38 is closed off by an externally threaded stub shaft 40 having aring or yoke 42 thereon. The rod 32 slidably extends through the stubshaft 40, and the other end of the rod engages a conventional thermalfuse element 44 positioned within the ring 42. The fuse element 44prevents movement of the rod 32 to the right as viewed in FIG. 1, untilthe heat of a fire fuses the element so that it collapses. Since thefuse element 44 is the standard type commonly used in conventionalsprinkler heads now on the market, it will not be described in greaterdetail.

The rod 32 has a piston head 46 mounted thereon which slidably engagesthe internal wall of the sleeve 38. A spring 48 is positioned betweenthe boss 34 and the piston head 46 to bias the piston head and the rod32 to the right with a predetermined biasing force.

With this arrangement, the piston head 46 and the rod 32 will be'drivento the right under the action of the spring 48 upon the fuse element 44collapsing in response to the heat of the fire. This unlatches the rod22 and allows it, along with the head assembly 24, to be expelled fromthe outlet orifice 16 of the body 12, and permit the water to spray outthrough the orifice.

It can be appreciated that the fusible member 44 is effectively isolatedfrom the interior of the body 12, so that it will not be influenced bythe moisture and low temperature conditions occurring therein due to thepresence of the water.

The details of the head assembly 24 are shown better in FIG. 2. Inparticular, the head assembly includes a relatively thick-walled tubularmember 50, the outer peripheral surface of which is spaced a smalldistance from the inner wall of the body 12. A pair of sealing rings 52and 54 are disposed in annular grooves formed in the peripheral surfaceof the tubular member and engage the inner wall of the body member 12.The rod 22 extends through the central bore of the tubular member 50,and an Oring 56 is disposed in an annular groove formed in the innerwall of the tubular member and engages the outer surface of the rod.

A sleeve 58 extends between the outer surface of the rod 22 and theinner wall of the tubular member 50, and flush with the bottom endsthereof, as viewed in FIG. 2. The sleeve 58 is formed of a fusiblematerial that fuses at a higher temperature than the fusible link 44 ofthe latching assembly 30. As an example, the sleeve 58 may be adapted tofuse at 1,000F., while the fusible link 44 may be selected to fuse at286F. In its non-fused condition, the sleeve 58 connects the tubularmember 58 to the rod 22.

The discharge head is incorporated in a fixed fire extinguishing systemmounted at or near the ceiling of the structure to be protected fromfire. In addition to several heads 10, the system will include a sourceof extinguishant and a network of pipes for supplying the extinguishantto the nozzles.

In operation the presence of a fire below the discharge head 10 of amagnitude to produce heat which will fuse the link 44 will collapse thelink and permit the spring 48 to force the rod 32 from its latchingposition with respect to the rod 22. As a result, the pressure of thewater in the body 12 will force the plug assembly 24, and therefore therod 22, outwardly from the body and thus permit a discharge of waterfrom the outlet orifice 16. The vanes 18a and 18b will impart a swirlingaction to the water as it discharges from the body 12 in a conventionalmanner, resulting in a continuous conical discharge spray pattern.

In the event the mechanical linkage assembly 30 becomes jammed, orotherwise inoperative, due to the presence of foreign matter such asrust, dirt, or the like, the collapse of the link 44 will not causedischarge of the rod 22 and the plug assembly 24 from the body 12 and aresultant discharge of water. However, upon the temperature of the firerising to the fusible temperature of the sleeve 58, the latter will meltand permit a release of the tubular member 50 from the rod 22. Thisresults in a discharge of the member 50 through the outlet orifice 16due to the pressure of the extinguishant in the body 12, and a resultantdischarge of the water in a normal manner.

It can be appreciated that even if the rod 22 remains jammed in the bodymember 12 after release of the rod 32, the above discharge of water willbe effected in response to the elevated temperature.

It is thus seen that the discharge head of the present invention isadapted for operation in a failsafe mode, which permits the automaticdischarge of water therefrom despite a breakdown in its normal operatingcomponents.

Although the above operation has been described in connection withspecific temperatures actuating the fusible link 44 and the fusiblesleeve 58, it is understood that these temperatures can vary inaccordance with particular design requirements.

Of course, other variations of the specific construction and arrangementof the discharge head disclosed above can be made by those skilled inthe art without departing from the invention as defined in the appendedclaims.

I claim:

1. A discharge head for use in a fixed fire extinguishing systemcomprising a body member having an inlet for connecting to a source ofextinguishant and an outlet for said extinguishant, a plug memberextending in said outlet, a rod connected to said plug member, controlmeans responsive to a predetermined fire condition in the vicinity ofsaid body member for permitting the release of said plug member fromsaid outlet, and a fusible material connecting said plug member to saidrod and adapted to fuse at a predetermined temperature to release saidplug member from said rod and permit the discharge of extinguishant fromsaid body member.

2. A discharge head for use in a fixed fire extinguishing systemcomprising a body member having an inlet for connecting to a source ofextinguishant and an outlet for said extinguishant, a plug memberextending in said outlet, a rod connected to said plug member, latchingmeans for engaging said rod to latch said plug member in said outlet,control means cooperating with said latching means and responsive to apredetermined fire condition in the vicinity of said body member forpermitting the release of said plug member from said outlet, and meansfor permitting the discharge of said extinguishant from said head inresponse to another fire condition different from said predeterminedfire condition.

3. A discharge head for use in a fixed fire extinguishing systemcomprising a body member having an inlet for connecting to a source ofextinguishant and an outlet for said extinguishant, a plug memberextending in said outlet, a rod connected to said plug member, a fusiblelink, a spring loaded member connected to said link and said rod, saidlink being adapted to collapse in response to a predetermined firecondition in the vicinity of said body member for permitting said springloaded member to disconnect from said rod and said plug member torelease from said outlet, and means for permitting the discharge of saidextinguishant from said head in response to another fire conditiondifferent from said predetermined fire condition.

4. A discharge head for use in a fixed fire extinguishing systemcomprising a body member having an inlet for connecting to a source ofextinguishant and an outlet for said extinguishant; means for closingsaid outlet; first fire responsive means responsive to a firstpredetermined fire condition in the vicinity of said body member foropening said outlet; and second fire responsive means responsive to apredetermined fire condition in the vicinity of said body member foropening said outlet.

5. The'discharge head of claim 4 wherein said fire conditions aretemperatures and wherein the temperature towhich said second fireresponsive means responds to is greater than the temperature to whichsaid first fire responsive means responds to.

6. The discharge head of claim 4 wherein said second fire responsivemeans is adapted to open said outlet in the event said outlet is notopened by said first fire responsive means despite occurrence of saidfirst predetermined fire condition.

7. The discharge head of claim 4 wherein said means for closing saidoutlet comprises a rod and a plug member connected to said rod andextending in said outlet.

8. The discharge head of claim 7 wherein said first fire responsivemeans comprises means for engaging said plug member in a manner toretain said plug member in said outlet and means responsive to saidfirst predetermined fire condition for permitting a release of saidengagement.

9. The discharge head of claim 7 wherein said first fire responsivemeans comprises latching means for engaging said rod to latch said plugmember in said outlet, a fusible link, and a spring loaded memberconnected to said link and said rod, said link being adapted to collapsein response to said first predetermined fire situation to permit saidspring loaded member to disconnect from said rod.

10. The discharge head of claim 7 wherein said second fire responsivemeans comprises a fusible material connecting said plug member to saidrod and adapted to fuse at a predetermined temperature to release saidplug member from said rod.

11. The discharge head of claim 4 wherein said head when the plug memberis released from said rod.

1. A discharge head for use in a fixed fire extinguishing systemcomprising a body member having an inlet for connecting to a source ofextinguishant and an outlet for said extinguishant, a plug memberextending in said outlet, a rod connected to said plug member, controlmeans responsive to a predetermined fire condition in the vicinity ofsaid body member for permitting the release of said plug member fromsaid outlet, and a fusible material connecting said plug member to saidrod and adapted to fuse at a predetermined temperature to release saidplug member from said rod and permit the discharge of extinguishant fromsaid body member.
 2. A discharge head for use in a fixed fireextinguishing system comprising a body member having an inlet forconnecting to a source of extinguishant and an outlet for saidextinguishant, a plug member extending in said outlet, a rod connectedto said plug member, latching means for engaging said rod to latch saidplug member in said outlet, control means cooperating with saId latchingmeans and responsive to a predetermined fire condition in the vicinityof said body member for permitting the release of said plug member fromsaid outlet, and means for permitting the discharge of saidextinguishant from said head in response to another fire conditiondifferent from said predetermined fire condition.
 3. A discharge headfor use in a fixed fire extinguishing system comprising a body memberhaving an inlet for connecting to a source of extinguishant and anoutlet for said extinguishant, a plug member extending in said outlet, arod connected to said plug member, a fusible link, a spring loadedmember connected to said link and said rod, said link being adapted tocollapse in response to a predetermined fire condition in the vicinityof said body member for permitting said spring loaded member todisconnect from said rod and said plug member to release from saidoutlet, and means for permitting the discharge of said extinguishantfrom said head in response to another fire condition different from saidpredetermined fire condition.
 4. A discharge head for use in a fixedfire extinguishing system comprising a body member having an inlet forconnecting to a source of extinguishant and an outlet for saidextinguishant; means for closing said outlet; first fire responsivemeans responsive to a first predetermined fire condition in the vicinityof said body member for opening said outlet; and second fire responsivemeans responsive to a predetermined fire condition in the vicinity ofsaid body member for opening said outlet.
 5. The discharge head of claim4 wherein said fire conditions are temperatures and wherein thetemperature to which said second fire responsive means responds to isgreater than the temperature to which said first fire responsive meansresponds to.
 6. The discharge head of claim 4 wherein said second fireresponsive means is adapted to open said outlet in the event said outletis not opened by said first fire responsive means despite occurrence ofsaid first predetermined fire condition.
 7. The discharge head of claim4 wherein said means for closing said outlet comprises a rod and a plugmember connected to said rod and extending in said outlet.
 8. Thedischarge head of claim 7 wherein said first fire responsive meanscomprises means for engaging said plug member in a manner to retain saidplug member in said outlet and means responsive to said firstpredetermined fire condition for permitting a release of saidengagement.
 9. The discharge head of claim 7 wherein said first fireresponsive means comprises latching means for engaging said rod to latchsaid plug member in said outlet, a fusible link, and a spring loadedmember connected to said link and said rod, said link being adapted tocollapse in response to said first predetermined fire situation topermit said spring loaded member to disconnect from said rod.
 10. Thedischarge head of claim 7 wherein said second fire responsive meanscomprises a fusible material connecting said plug member to said rod andadapted to fuse at a predetermined temperature to release said plugmember from said rod.
 11. The discharge head of claim 4 wherein saidmeans for closing said outlet comprises plug means extending in saidoutlet and a link member adapted to retain said plug means in saidoutlet, said first and second fire responsive means each cooperatingwith said link member in a manner to permit release of said plug meansfrom said outlet in response to said first predetermined fire conditionand said predetermined fire condition, respectively.
 12. The dischargehead of claim 9 wherein said plug member is arranged and constructed tobe expelled from the outlet by the pressure of extinguishant in saidhead when the plug member is released from said rod.